1. Field of the Invention
This invention relates to an intake valve for use in a four cycle internal combustion engine to increase volumetric efficiency, and specifically to a primary poppet intake valve with apertures that uses three or more secondary poppet valve bodies for opening and sealing said primary valve face, said primary poppet valve face opening and sealing a single intake duct and port seat.
The sum of the circumferential distances of the secondary poppet valves are specifically determined to accelerate valve opening value (circumference times lift) throughout the intake event, also simultaneously extending the duration of optimum valve opening area during the critical time frame of maximum piston velocity.
The purpose of the invention is to quantitatively increase the intake valve open area value (circumference times lift) of a single intake duct/port to enhance optimum charge flow into the combustion chamber during the intake event resulting in greater volumetric efficiency when compared with the valve open area value at varying lift points available with a single conventional intake poppet valve.
2. Description of Related Art
The use of one or more poppet intake valves in a single engine cylinder in a four cycle internal combustion engine is well known in prior art. Typically each intake duct and its corresponding port is serviced by one conventional intake poppet valve. The cross sectional area of the duct/port and the valve area value achieved (lift times circumference) at maximum valve lift generally match or exceed duct/port area to prevent impedance of the charge flow velocity during expurgation of same into the cylinder. Since the correct maximum valve open area value is the valve body circumference times maximum lift, conventional valve lift distances exceeding 0.350 thousandths inch are generally employed in engines of 500 cubic inches or less. Such lift distances encroach the mechanical limits of the cam lobe profile and the valve train components due to constraints during the intake event. The result is that maximum valve opening is achieved during a limited instantaneous position over the entire intake event's duration at the cam lobe profile. In essence during the intake event, the maximum charge available in the intake duct as determined by its cross sectional area is not provided to the cylinder throughout the major portion of the intake event.
Applicant's invention differs significantly from the conventional intake valve technology in that three or more secondary poppet valve bodies sealable to apertures are employed within a primary valve structure, said system to function in communication with a single duct/port resulting in an increased total valve circumference utility, thus defining an extended valve circumference, expanding valve open area values available throughout the intake event for an improved flow from a single duct/port, greatly increasing the volumetric efficiency of the engine.